Classification
Classification of diamond to I a and II a groups using Diamond Spotters and Diamond Illuminators for precise separation of the diamonds of the two groups.
Group A: type IaA, IaAB and Ib
Such colorless diamonds have not been decolorized by a HPHT treatment.
Group B: type IIa, IIb and rare IaB
Such diamonds may have been treated by a HPHT treatment.
If a diamond results in a type Ia no further investigation is done. If a diamond is type IIa then investigation for treatment HPHT takes place.
The diamond spotter initially has been developed as a reaction to the threat of the HPHT treated diamonds. You may test all diamonds with the diamond spotter. Be it colorless or colored, cut or rough crystal, loose or mounted. Even diamonds which are larger than the sample holder of the spotter may be tested.
Type II diamonds are found as colorless (type IIa), pink (IIa), blue (IIb) or brown (IIa and IIb) stones. Colorless, pink or blue stones may be naturally colored or the result of a High Pressure High Temperature treatment (HPHT).